Category: peptide
Aliases: PP, Human PP, hPP
36-residue peptide released from pancreatic islet F-cells (at periphery of islets), especially postprandially under strong vagal control. Member of the NPY / PYY / PP family with a characteristic PP-fold (hairpin polyproline-II + α-helix stabilised by hydrophobic packing). Binds Y4 receptor preferentially (minor activity at Y5). Postprandially contributes to satiety and reduces gastric emptying + pancreatic exocrine secretion. Elevated basal PP is a hallmark of PPomas (rare functional NET). Not developed as a drug — circulating PP analogs have been research-probed for obesity with limited success.